Asking players whether they want a sabbatical clause in their NZRU contract can, at times, be a touchy subject.

OPINION:
Some are reluctant to go there. Others, like Sam Whitelock, are more forthright.

One thing is certain: it's not an issue that will go away.

If the NZRU are to hold their most influential All Blacks they aren't likely to risk losing them by insisting they keep powering through the Super Rugby and test calendars. Something has to give.

The sabbatical clause remains one of the NZRU's most important bargaining chips.

Either a player signs an overseas contract or continues to offer some value to New Zealand by going on holiday or topping up their earnings on a short-term foreign contract for the sort of coin the NZRU cannot match.

Dan Carter and Richie McCaw have been there. Conrad Smith will take a break at the end of the year. Keven Mealamu returned to the Blues late this year following an extended summer off-season.

We are likely to hear more, not less, about sabbaticals ahead of the 2015 World Cup. Kieran Read, who is being groomed to take over from McCaw, could be offered a deal that allows him to take a break after the global tournament.

Whitelock, set to be a central pillar in the All Blacks' quest to retain the Webb Ellis Cup, may want something similar if he wants to play the Lions in 2017.

Getting the balance right is crucial for the NZRU.

The granting of sabbaticals needs to reserved for the game's most loyal, and talented, servants.

The NZRU should make it clear it will never be doled out to a journeyman or a kid who shows immense promise. They cannot be held to ransom.

Super Rugby coaches also need to be respected, and kept informed- not to mention the fans.